Danny Williams, who spent years as a lightly regarded contender before stunning Mike Tyson, said he will test the heart and chin of Vitali Klitschko in their WBC title fight here tomorrow.
A confident Williams says Klitschko lacks the fighting spirit necessary to successfully defend his WBC heavyweight title at the Mandalay Bay Resort and Casino tomorrow.
"Klitschko has a yellow streak in him," the 31-year-old Williams said.
"He does not like it when things get tough. His heart is definitely a weakness and it is up to me to expose it once again," he said.
Williams is trying to validate his shocking win over Tyson five months ago.
Klitschko, of the Ukraine, has had to live with the tag of "quitter" since refusing to get off his stool at the end of the ninth round of his WBO title defense against Chris Byrd in April 2000.
He tore his left rotator cuff earlier in the bout and later underwent surgery.
Williams has gone 12 rounds five times in his 35-fight career while the 33-year-old Klitschko (34-2) has done it just once.
Williams points to his amazing 2001 British title battle with Mark Potter in which he dislocated his right shoulder but fought on despite mounting calls from ringside for him to give up.
In the sixth round, Williams let fly with a crashing left hand that sprawled Potter semi-conscious on the canvas.
"I never thought I would knock out Potter with my right arm as bad as it was," he said.
"I proved that when I was in a situation like that, I did not feel pressure so I could perform at my best," Williams said.
"But Klitschko only half-hurt his shoulder near the end against Byrd when he was way ahead on the scorecards. He just pulled out and said he would live to fight another day. Those are not the words of a true warrior," he said.
Williams' trainer, Jim McDonnell believes the university-educated Klitschko is too bright to fight through adversity.
He added that while most top fighters rely solely on instinct in desperate situations, Klitschko remained cold and measured.
"Klitschko is a very wise individual. I think he is so wise that during the Byrd fight he made a business decision," he said.
"He decided he would get his chance at the title again and it was not worth carrying on," McDonnell said.
Klitschko has refused to be drawn into arguments over his fighting spirit.
He believes he proved a point last year when he was willing to fight on against Lennox Lewis before the fight was stopped because of cuts.
"People are entitled to their opinion," he said.